The invention relates in general to printing presses and in particular to a new and useful device for loading and unloading paper rolls of a roll stand equipped with swivel arms of a web-fed rotary printing press using a traveling platform unit equipped with a lifting device and movable in the horizontal direction.
A similar loading and unloading device is shown, for example, in German OS 34 02 582. For loading the roll stand, a new paper roll is brought onto a lift device of a traveling platform unit built as a lift platform, the traveling platform unit being outside the area of the roll stand. The traveling platform unit then drives in a horizontal direction between the swivel arms of the roll stand, whereupon the lift platform lifts the paper roll to the required height. The paper roll clamping devices on the swivel arms can then reach into the central core opening of the paper rolls. The paper rolls, which can be very heavy depending on the dimension, must, for this insertion, be aligned exactly between the swivel arms of the roll stand, so that the paper roll clamping device can reach into the core opening of the paper roll. This aligning is still frequently done by hand, which requires operating personnel while being tied to a great deal of energy expenditure. Automatically building the paper rolls into the roll stand is not possible. Furthermore, on changing production as well as on continuous processing of the paper web, a residual paper roll of given diameter results, which before reloading the roll stand with a new paper roll must be removed from the roll stand.
Since in the head of the swivel arms of the roll stand, in addition to the mounting of the paper roll clamping device, additional apparatus like a shift mechanism of the paper roll clamping device, paper roll breaks, clamping device at the paper roll clamping journal, regulated drive of the paper roll clamping journal, are located, this head, understandably is of considerable size. And, since the swivel arms of the roll stand have to be able to accept paper rolls of different widths because of the different widths of the paper web, the swivel arms are constructed movable. The lift platform of the traveling platform unit, however, has to be constructed in such a way, that it can feed the widest paper roll or that a small paper roll can be processed on the left as well as on the right margin of the press.
With the prior traveling platform units with lift platforms only material up to a certain size, depending on the dimensions of the head of the swivel arm of the roll stand, can be lifted up to the paper roll bearing axle. Residual rolls of small diameter would, on unloading, have to be dropped a given distance onto the lift platform on unloading, which can lead to damage to the paper rolls and lead to disturbances during automatic roll changing. On the other hand, residual rolls, which have a relatively small diameter and which still need to be processed, can no longer be brought automatically between the swivel arms of the roll stand.